Traditional decorative items displayed during holiday seasons include lights, ornaments, figurines, and other displays. Some decorative items of this type require a power source and electrical circuitry to provide illumination, motion, sound, and so on. For example, most decorative light strings adorning Christmas trees are powered by plugging the light string directly into an alternating current (AC) source provided by an adjacent light string, a switched outlet, or some other nearby AC power supply.
Alternatively, ornaments and some tree top lights placed on a Christmas tree may utilize a direct current (DC) power source such as a battery or other self contained/self powered system which does not require power from the AC/electrical network. The DC power source may be used to power a light source, rotate a motor shaft, play a recording, or perform some other function requiring electrical energy. For example, a tree top decoration placed at the pinnacle of a Christmas tree may be lit with a series of incandescent lights or light-emitting diodes (LEDs). Ornaments hung on a Christmas tree may spin in circles or move up and down, when power is switched on. Individual figures displayed on a table top may similarly move, “speak”, or be lit using battery power. For such devices, the use of batteries as the source of DC power eliminates the need for bulky power cords, removes constraints on item location, and increases overall safety.
Despite the advantages of using DC power to power decorative displays, certain drawbacks exist. For example, when the number of battery-operated items displayed becomes large, manually switching each battery-operated device on and off becomes time-consuming and may disrupt the arrangement of the display. This becomes especially true when multiple battery-operated ornaments are displayed on a tree, or multiple figurines displayed on a table-top. Similarly, some decorative displays may not be within easy reach of the user, such as a lighted tree top display placed on the top of a tall tree, or an ornament placed at an inconvenient location on a tree. In addition to the inconvenience of having to manually switch display items on and off, items may become broken in the process due to repetitive handling, or may never be turned off, thereby wasting energy. With battery operated devices, energy conservation is a necessity. Thus is would be desirable to be able to turn on/off such devices remotely and to further intelligently control their actuation to create interesting effects.
Some prior inventions have attempted to address some aspects of these problems through the use of electromagnetic field (EMF) generation. Generally speaking, when an AC current flows through a conductor, an electromagnetic field is generated. The electromagnetic field comprises a magnetic and an electric field. An antenna 28 place near the source of the EMF will receive the EMF signal and a voltage and current generated at the antenna.
In one prior example, U.S. Pat. No. 5,118,196, issued to Ault et al., discloses a system that uses an AC-powered EMF generator to transmit oscillating radio-frequency EMF through a Christmas tree. In another example, U.S. Pat. No. 5,034,658 also employs a powerful EMF generator to provide oscillating power to light-emitting elements.
Such prior inventions directly power the targeted decorative items with the emitted oscillating EMF, which means that the power to the decorative item fluctuates with the frequency and amplitude of the EMF signal. Generally, this creates a flickering effect, which may not be desirable. Furthermore, a pinpoint source of EMF is prone to interference, with items further from the source operating less consistently. Other issues of concern include EMF exposure, space consumption, aesthetic appeal, and so on. As such, these types of systems have not been commercially popular.
At least one prior invention has tried to capture the use of ambient EMF generated by nearby AC powered devices to power a string of animated ornaments. U.S. Pat. No. 5,317,238, issued to Schaedel, discloses a series of ornaments wired together and powered by a DC source. The Schaedel invention uses EMF to light LEDs within the ornaments. The device in Schaedel relies on, and is limited to using CMOS counters to detect EMF and power LEDs in a rotating sequence to create an oscillating effect. Although this type of invention attempts to take advantage of ambient EMF generated by nearby devices, it still fails to address all of the problems previously discussed.
As such, there exists a need in the industry for decorative displays that can solve the problems described above.
While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.